## Following extract the first initial character only:
sed 's/\(.\).*/\1/' input_file > $$FirstChar
## Following extract from the second character on:
sed 's/.\(.*\)/\1/' input_file > $$OtherChars
## Following changes the first character to upper case:
tr '[a-z]' '[A-Z]' < $$FirstChar > $$UpperChar
## Following paste together the upper case character and
## the other characters:
paste -d'\0' $$UpperChar $$OtherChars
## Following removes temporary files:
rm -f $$*